The Anvil-Thane's Designs

For this questline you need to be on your Dark Iron Dwarf (lvl 50+) and currently it has to be the DID that did Heritage of the Dark Iron.
Use your Mole Machine to get there, it's in your general spell tab. Select Eastern Kingdoms > Shadowforge City.

1. 
   
2. The Anvil-Thane's Designs - turn around and walk forward, upstairs, follow the way on the right side (don't jump down) and enter the Grim Guzzler
3. 
   
4. Brawl or Brew - click her dialogue and select "brawl". Fight against [npc=26125]
5. 
   
6. It's Called Borrowing - go down and kill [npc=176995] for [item=184916]. Go back to the ramp where you came from and collect 5 [item=184915], they lie around in the big marked area near the [npc=144132]s. Follow the way until you reach Kasea Angerforge and ask her for the [item=184917]. Turn around and go back a bit to turn in the quest
7. 
   
8. Weapons o' the Dark Iron - talk to [npc=144154] and click the darkforged ingot
   Turn in and get [item=184922].
9. 
   
10. Delivery for Kasea - follow the way back
11. 
    
12. Good Fiery Boy - click [npc=185352] next to you, throw it on the ground and click [npc=185305] to pet him. Collect 4 [item=190606] from the boxes and feed him. After that, click the extra action button [spell=367727].
    Turn in and get [item=191123].
13. 
    

Questline took about 15 minutes with level 52 and ilvl 85.

If you haven't explored this instanced version of BRD much yet, instead of heading towards the question mark on your minimap, go north-east from Thurgaden to find a way to the upper level, which allows entrance into the Grim Guzzler.

I did this on my Rogue, and YES, my other characters could use the weapons that were 'unlocked' but not usable by the Rogue (e.g, Shield, Staff). Hooray. One Dark Iron to unite all the transmogs.